Diplocephalus connatus
Key Details
| Taxonomic Groups: | Invertebrate > spider (Araneae) > Spider |
| Red List Status: | Critically Endangered (Not Relevant) [CR(nr)] |
| D5 Status: | Included in the baseline Red List Index for England (Wilkins, Wilson & Brown, 2022) |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Diplocephalus connatus |
| UKSI Recommended Authority: | Bertkau, 1889 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Harvey et al., 2017 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | CR, criteria: B2ab(ii,iv): last recorded in 1996 (new hectad) despite recent targeted searches at all former sites. Entire known GB population recorded from England despite it being a N, river shingle species. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Extremely rare even in relation to its specialised habitat and localised geography |
| Question 3: | At a landscape scale, would the species benefit from untargeted habitat management to increase habitat mosaics, structural diversity, or particular successional stages? |
| Response: | No |
| Justification: | This species would not benefit from untargeted management |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 2. Biological status assessment exists |
| Recovery potential/expectation: | Low - Extinction debt |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | Found in voids under rocks on exposed, sandy river shoals. |
Key Actions
Key Action 1
Proposed Action: Intensive targeted survey of previous areas and of similar river shoals on other N rivers
Action targets: 2. Biological status assessment exists
Action type: Status survey/review
Duration: 2 years
Scale of Implementation: ≤ 10 sites
High priority sites: Sandy shingles on the Tyne and Allen
Comments: Need to resolve access issues via private riparian land holdings. Relates to actions for Cavephantes saxetorum.
Key Action 2
Proposed Action: Reduce upstream sewage pollution; particulates smother shingle and eutrophication changes entire community.
Action targets: 5. Remedial action identified
Action type: Pressure mitigation
Duration: 3-5 years
Scale of Implementation: National
High priority sites: Rivers Tees and Allen and Tyne
Comments: Add in any other rivers where it is discovered (Action 1). Combine action with that for Cavephantes saxetorum.
Key Action 3
Proposed Action: Control INNS (particularly Himalayan Balsam and Japanese Knotweed) at known and potential sites.
Action targets: 5. Remedial action identified
Action type: Pressure mitigation
Duration: Unknown
Scale of Implementation: National
High priority sites: Initial focus on Rivers Tees and Allen and Tyne
Comments: Combine action with that for Cavephantes saxetorum. Action likely to be absorbed within local INNS control initiatives.
Acknowledgment:
Data used on this website are adapted from Threatened species recovery actions 2025 baseline (JP065): Technical report and spreadsheet user guide (Natural England, 2025). Available here.